Surfactants are broadly used as wetting agents in waterborne formulations. Alkylphenol ethoxylates (APEs) are widely recognized as good surfactants in a large variety of applications. APE surfactants, however, suffer from a poor public perception of their environmental compatibility. In addition, they are subject to increasing environmental regulation aimed at reducing their consumption in many applications, including in emulsion polymerization (EP). Therefore, the use of APE type surfactants is declining and suppliers are seeking to provide other surfactants to replace them.
Emulsion polymerization (EP) is a polymerization process in which poorly water soluble monomers are emulsified in water with the aid of emulsifiers and then polymerized with initiators. Surfactants play a key role in emulsion polymerization and in particular, APE based surfactants are generally considered the standard. However, in view of the issues with APE surfactants as discussed above, there is a need for new non-APE materials that exhibit properties suitable for emulsion polymerization. Such properties may include reduced foaming, emulsion formulation stability, and mechanical stability.
The problem addressed by this invention is the provision of new surfactants that are commercially viable alternatives for APE materials in emulsion polymerization.